The double-alloy screw (bimetal) screw base material is an alloy structural steel, and the Jinyang double alloy screw is divided into two types: (1) A prismatic double alloy screw means that a layer of wear-resistant and corrosion-resistant alloy is melt-spray-jet welded on the surface of the screw edge. (2) Full-spray twin-alloy screw means that the screw and groove are entirely sprayed with a layer of wear-resistant, corrosion-resistant, and high-temperature-resistant alloy; the hardness of the screw surface alloy is higher than the hardness of the substrate; the main component of the double-alloy screw of Jinyang is the United States. Imported tungsten carbide (Wc/Co) nickel-base alloy (Ni+B/Cr), self-fluxing alloy; using ion welding dual alloy process, the advantage is to improve the hardness of the screw surface and wear, corrosion resistance, high temperature performance. Jinyang screw-double alloy screw is mainly used for adding glass fiber plastic, VO fireproof material, PA, PC, PBT, PPO, PC + ABS and other glass fiber engineering materials.